Hand-held tool for cutting laminated glass and film-covered glass and method for using same

ABSTRACT

An apparatus for cutting laminated glass and film-covered glass includes a powered hand-held tool with a blade set including two static cutting blades and one dynamic, reciprocating cutting blade. The reciprocating cutting blade moves between the two static cutting blades which are rigidly mounted to the tool head. The left and right static cutting blades were spaced apart by about 0.250 inches, and the cutting blade had a thickness of about 0.200-0.250 inches. The clearance between the reciprocating and each static blade is between about 0.005-0.025 inches.

RELATED APPLICATIONS

This application claims priority to U.S. provisional patent applicationSer. No. 61/549,345 filed Oct. 20, 2011, entitled “A Hand-Held Tool ForCutting Laminated Glass And Film-Covered Glass And Method For UsingSame.”

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a relates to a hand held tool forcutting laminated glass and film-covered glass, such as automotivewindshields and architectural windows, and an associated method forcutting laminated glass and film-covered glass.

2. Background Information

Laminated glass, which is a type of safety glass, utilizes two or moreregular or specially strengthened glass sheets bonded together with aspecial plastic interlayer to form a clear, see-through barrier withenhanced impact and shatter resistance. Polyvinyl butyral (PVB) plasticis commonly used as the interlayer which enhances the glass further byincreasing sound insulation and blocking nearly 99% of ultravioletradiation. The interlayer maintains the layers of glass bonded even whenbroken, and the relative high strength of the interlayer prevents theglass from breaking up into large sharp pieces. This produces acharacteristic “spider web” cracking pattern when the impact is notenough to completely pierce the laminated glass. Laminated glass isnormally used when there is a possibility of human impact or where theglass could fall if shattered. Laminated glass is standard in automobilewindshields and is routinely used in building architectural windows orcurtain walls (a non-structural outer covering of a building),skylights, and in prisons. More recently, laminated glass is used forblast and hurricane protection for architectural windows.

Automobile windshields are a clear, see-through wind barrier whichprovides impact resistance from insects, road debris, vandalism, etc . .. , roof crush resistance, airbag support and resistance to occupantejection. Windshields can become damaged during normal use and duringvehicle crashes. When windshields fracture, the glass fragments arecontained and occupant injury risk is minimized. It should be noted thatthe term windshield is used generally throughout North America while theterm windscreen is the usual term in the British Isles and Australasiafor all vehicles. Rear windows of automobiles are also constructed ofglass laminates.

During automobile crashes, there are instances when the vehicleoccupants become trapped within the vehicle, possibly in need ofemergency assistance, but where the occupants cannot be accessed via thedoors. When this occurs, emergency personnel are required to remove thewindshield or rear window to access the occupants. There are two methodsemployed for windshield removal: 1) blunt impact or 2) cutting. Bluntimpact with an object like a hammer or a fire axe can fracture or tearthe windshield. Handheld or powered saws can cut windshield glass aftercreating an access hole. Each of these methods increases the risk ofinjury to the patients/vehicle occupants and/or the emergency personnelby flying glass debris and increased extrication time. The power sawsadditionally create a large amount of harmful silica dust, discussedfurther below, as it ribs apart a ribbon of the windshield that isslightly wider than the saw blade.

During normal use, windshields can become damaged by impacts from roaddebris or other materials and require replacement. After replacement,the vehicle inspection stickers must be replaced or transferred from theold windshield. Technicians routinely transfer the inspection stickersintact with a portion of the windshield by trimming the glass,protecting the sharp edges with tape and placing them on the vehicledashboard. This process can be time consuming and increases the risk ofpersonal injury.

Plastic films are commonly used to cover laminated and un-laminatedglass to provide additional resistance to impact, fire, UV light, soundand blast.

Silica is a mineral compound made up of one silicon atom and two oxygenatoms (SiO₂). Crystalline silica is formed when silica molecules arelined up in order and in crystal form. Crystalline silica is a componentof glass and has been used in many other industries such as blastfurnaces, cement manufacturing, glass and concrete mixing productmanufacture, ceramics, clay, china pottery, electronic, foundry,sand-blasting and manufacturing abrasives, and many constructionactivities. Occupations having a high potential for exposure tocrystalline silica dust (aka respirable quartz) are metal, coal, andnonmetal (except fuels) mining; foundry, stone clay, and glassproduction work; and agricultural, chemical production, highway repair,and tuck-pointing work. Thus silica dust is a known inhalation hazard.Workers may be at risk of silicosis from exposure to silica dust whenhigh-velocity impact shatters the sand into smaller, respirable (<0.5 to5.0 μm in diameter) dust particles. According to the American ThoracicSociety silicosis is a disease where scar tissue forms in the lungs andreduces the ability to extract oxygen from the air. Symptoms ofsilicosis can be acute, accelerated, or chronic. According to theNational Institute for Occupational Safety and Health acute silicosismay develop within weeks and up to 5 years after breathing large amountsof crystalline silica. Accelerated silicosis may develop shortly afterexposure to high concentrations of respirable crystalline silica,whereas chronic silicosis occurs after 10 years of exposure torelatively low concentrations of crystalline silica. OSHA has estimatedthat more than 2 million workers are exposed to crystalline silica dustin the general, maritime, and construction industries, and that morethan 100,000 workers have high-risk exposure to airborne silica dustthrough construction and mining operations. Further it has beenestimated that there were an estimated 3,600-7,300 newly recognizedsilicosis cases per year in the United States from 1987 to 1996 and thatbetween 1990 and 1996, 200-300 deaths per year were known to haveoccurred where silicosis was identified as a contributing cause on deathcertificates. Further, the International Agency for Research on Cancerclassified crystalline silica as a known human carcinogen with exposureto crystalline silica associated with an increased risk of developinglung cancer. Previous studies also documented an association betweenairborne silica exposure and other health problems, including chronicobstructive pulmonary disease, rheumatoid arthritis, scleroderma,Sjogern's syndrome, lupus, and renal disease.

In fields other than glass, shearing tools have been designed such asdisclosed in U.S. Pat. No. 7,637,016, which is incorporated herein byreference, which discloses hand-held cutting tools used to cutfiber-cement siding. U.S. Published Patent Application 2006-0213343,which is also incorporated herein by reference, discloses waste ejectingblade assemblies for hand-held cutting tools and methods for cuttingfiber-cement materials. U.S. Published Patent Application 2004-0050223,which is also incorporated herein by reference, discloses bladeassemblies for reciprocating wallboard tools and methods for cuttingwallboard. See also U.S. Published Patent Application 2003-0029043,Design Pat. D443,806, U.S. Pat. No. 5,993,303, U.S. Pat. No. 5,992,024,U.S. Pat. No. 5,566,454, U.S. Pat. No. 4,173,069, U.S. Pat. No.3,808,682, and U.S. Pat. No. 2,934,822 which are also incorporatedherein by reference. These tools provide certain advantages for theirparticular designated work products but fail to provide effective orefficient, or even useful, laminated glass cutting tools as the bladesets of these tools tend to crush the glass layers without shearing thelaminating layer resulting in a jammed tool when attempted to beimplemented with laminated glass.

A refined method for cutting laminated glass and film-covered glasswould minimize personal injury associated with vehicle occupantextrications, as well as laminated glass and film-covered glass repairand replacement. Further, the time needed for cutting will be greatlyreduced. Further there is a need to perform such glass processing in amanner that minimizes airborne silica, particularly for Emergencyworkers, whom do not always take the time needed to don mask or otherprotective equipment when responding to a vehicle crash.

SUMMARY OF THE INVENTION

One aspect of this invention is directed to an apparatus for cuttinglaminated glass and film-covered glass and an associated method forcutting laminated glass and film-covered glass. A laminated glass andfilm-covered glass cutting tool in accordance with this invention mayhave a hand-held motor unit with a housing, a motor inside the housing,and a switch operatively coupled to the motor to selectively activatethe motor. A head having a casing may be attached to the housing of themotor unit. The head may also have a reciprocating drive assemblycoupled to the motor.

To meet the need for a laminated glass and film-covered glass cuttingtool, the present inventor developed a powered hand-held tool with ablade set including two static cutting blades and one reciprocatingcutting blade. The reciprocating cutting blade may be powered, as onerepresentative example, by a Pacific International Tool & Shear,Kingston, Wash. (Model No. SS504). The reciprocating cutting blade movesbetween the two static cutting blades which are rigidly mounted to thetool head. The left and right static cutting blades were spaced apart by0.250 inches, and the cutting blade had a thickness of 0.200-0.250inches. The clearance between the reciprocating and each static blade isbetween 0.005-0.025 inches.

When cutting laminated glass and film-covered glass in accordance withthe present invention, the glass is placed between the open tips of thereciprocating and static cutting blades. The reciprocating cutting blademoves from the open to closed position causing shearing along both sidesof the blade to form a cut approximately as wide as the gap between theleft and right static blades. The hand tool operator would translate thetool as required as the blade reciprocates between the open and closedpositions to cut the laminated glass in a progressive fashion.

The hand-held cutting tool also has a blade set with first and secondstatic blades attached to either the casing or the motor housing, and areciprocating cutting blade between the first and second static blades.The first static blade may have a first guide surface and a firstinterior surface. Similarly, the second static blade may have a secondguide surface and a second interior surface. The first and second guidesurfaces are preferably in a common plane, and the first and secondinterior surfaces are spaced apart from one another by a gap distance.The reciprocating cutting blade has a body with a first widthapproximately equal to the gap distance and a blade projecting from thebody. The blade has a first side surface facing the first interiorsurface of the first static blade, a second side surface facing thesecond interior surface of the second static blade, and a top surface.The first side surface of the blade is preferably spaced apart from thefirst interior surface of the first finger by 0.005-0.025 laminatedglass. Similarly, the second side surface of the blade is spaced apartfrom the second interior surface of the second static blade by0.005-0.025 inches.

The top surface of the reciprocating cutting blade may range from flatto angled to concave and may vary with serrations. The reciprocatingcutting blade profile may range from straight to curved with single tomultiple radii.

It is noted that, as used in this specification and the appended claims,the singular forms “a,” “an,” and “the” include plural referents unlessexpressly and unequivocally limited to one referent. The features thatcharacterize the present inventions are pointed out with particularityin the claims which are part of this disclosure. These and otherfeatures of the invention, its operating advantages and the specificobjects obtained by its use will be more fully understood from thefollowing detailed description and the operating examples.

These and other advantages are described in the brief description of thepreferred embodiments in which like reference numeral represent likeelements throughout.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is schematic isometric view of a laminated glass cutting tool anda blade set engaging a work piece in accordance with one embodiment ofthe invention;

FIG. 2 is a schematic side elevation view of the blade set of FIG. 1;

FIG. 3 is a schematic top plan view of the blade set of FIG. 1;

FIG. 4 is a schematic side elevation view of a dynamic blade of amodified blade set for use in the laminated glass cutting tool of FIG.1;

FIG. 5 is a schematic side elevation view of the blade set of FIG. 4 ina closed position; and

FIG. 6 is a schematic side elevation view of the blade set of FIG. 4 inan open position.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention is an apparatus and associated method for cuttinglaminated glass and film-covered glass, such as commonly found inautomobile windshields and many laminated architectural windows. Manyspecific details of certain embodiments of the invention are set forthin the following description and in FIGS. 1-6 to provide a thoroughunderstanding of such embodiments. One skilled in the art, however, willunderstand that the present invention may have additional embodiments,or that the invention may be practiced without several of the detailsdescribed in the following description.

FIG. 1 is a schematic isometric view of a hand-held cutting tool (10)for cutting a laminated glass or film-covered glass work piece (W). Thecutting tool (10) has a housing (20), a drive system (30), a head (40)and a blade set (50).

The housing (20) has a casing (21) which contains the drive system (30),a motor control switch (22) which is operatively coupled with the motor(31) of drive system (30) and a handle (23) for operator gripping. Thehousing (20) is a hand held unit and preferably operable with a singlehand, to allow the user additional freedom, which may be critical in anemergency situation. The housing (20) has the shape of many hand heldpower tools, which also assists in making the operation of the tooleasily and immediately understood by operators, which can be furtherhelpful in emergency situations. Thus there will be no time lost byemergency response personnel, whom would not be expected to utilize thetool (10) daily, re-familiarizing themselves with the operation of thetool (10).

The system or tool (10) can be battery powered as shown, withrechargeable battery pack (not shown), such as a 14.4 V 3.0Ah li-ionbattery, received within the handle (23), as generally known in the art.The rechargeable battery pack will typically last for the removal ofabout 20 automotive windows on a single charge. The tool (10) can alsobe run from a plug in power source (e.g. conventional 110 v socket) viacord (not shown) also going to handle 23. The battery powered version ofthe tool (10) as shown is generally preferred for field applications(e.g. automobile windshields in the field), however the cord version oftool (10) can be acceptable for garage applications, or for use inreplacing architectural laminated windows. It is also anticipated thatthe power supply for a given tool (10) could be either a battery pack orplug in cord as selected by the user via appropriate adaptor.

The drive system (30) contains a motor (31) and a transmission (32). Thehead (40) contains a casing (41) which may be mounted to the housing(20) and/or the drive system (30). The transmission (32) of the drivesystem (30) converts the rotational power of the motor (31) intoreciprocating motion such as via an eccentric cam to drive the blade set(50). The details of the drive system (30) are generally known in theart and alternative known designs may be implemented provided theyprovide the needed power, reciprocation rate and can be easilyincorporated into a hand held housing (20). As noted above a PacificInternational Tool & Shear, Kingston, Wash. (Model No. SS504) forms anacceptable base for tool (10), this is also known as PacToolInternational and sell under the SNAPPER SHEAR™ brand for shear basedtools.

The blade set (50) may consist of a left static cutting blade (51)mounted on the left side of the head (40), a right static cutting blade(52) mounted on the right side of the head (40) and a dynamic blade (53)pivotally coupled between the left (51) and right (52) static cuttingblades. The blade set (50) can be formed of any suitably hard material;however tool steel is likely due to the ability to maintain a sharpshearing or cutting edge. Tool steel refers to a variety of carbon andalloy steels that are particularly well-suited to be made into tools.Their suitability comes from their distinctive hardness, resistance toabrasion, their ability to hold a cutting edge, and/or their resistanceto deformation at elevated temperatures (red-hardness). With carboncontent between 0.7% and 1.5%, tool steels are manufactured undercarefully controlled conditions to produce the required quality wellsuited for holding the tight tolerances needed for blade set (50). Atypical blade set (50) will maintain a high level of sharpnesssufficient for about 50 automotive windshields, after which the bladescan be refurbished for further use.

The reciprocating motion provided by the transmission (32) inside thehead (40) drives the dynamic blade to generate cutting forces on thework piece W against the left (51) and right (52) static cutting blades.The head (40) encompasses the blade set (50) using the forward fastenerset (42), the middle fastener set (43) and the aft fastener set (44).

FIG. 2 is schematic side view of the blade set (50) and FIG. 3 is aschematic plan view of the blade set (50) used with the laminated glassand film-covered glass cutting tool (10). The left static cutting blade(51) contains a right interior surface (51 a) and a lower cuttingsurface (51 b). The right static blade (52) contains a left interiorsurface (52 a) and a lower cutting surface (52 b). The dynamic cuttingblade (53) contains a body (53 a), a blade (53 b), a left exteriorsurface (53 c), a right exterior surface (53 d) and an upper cuttingsurface (53 e).

The cutting surfaces (left—51 a, right—52 a) of the static cuttingblades (left—51 and right—52) and the cutting surface (53 e) of thedynamic cutting blade (53) may contain straight, curved or variableshapes along their respective lengths and may contain concave,trapezoidal or variable shapes along their blade cross sections. Thedetails of the dynamic cutting blade (53) are described in greaterdetail in connection with FIGS. 4-6.

FIG. 4 is a schematic side elevation view of a dynamic blade (53) of amodified blade set (50) for use in the laminated glass cutting tool (10)of FIG. 1 and FIGS. 5 and 6 are schematic side elevation views of theblade set (50) of FIG. 4 in a closed and open position, respectively toillustrate the stroke or bite of the tool (10). In FIG. 4 the dynamicblade (53) includes an opening (56) for bushing (54) to receive a pivotaxel or there through. As best illustrated in comparing the cuttingsurface (53 e) of the dynamic cutting blade (53) between the open andclosed positions of FIGS. 6 and 5, the cutting surface (53 e) includes acentral main cutting section (57) that performs the substantialshearing, an immediate chip guiding surface (58) following the cuttingsection (57) and a guide in surface (58) immediately before the cuttingsection (57). The operating throat of the tool, as shown, moves between0.566″ and 0.285″ in this embodiment and the tool is intended to takesmall, extremely rapid “bites” or cuts from the work piece. As shown,generally less than 20% of the effective blade length (distance from tipto the intersection of the cutting edges of the static blades (51 and52) and the dynamic blade (53) in the open position of FIG. 6), formsthe cutting section (57) and often 10-15% of the effective blade lengthforms the cutting section (57).

In front of the cutting surface (53 e) is a lead in surface (60) thatextends to a blunted tip (61), as shown. The blades (51, 52 and 53) ofthe blade set (50) include the blunted tip (61) construction as shown tofacilitate using the tool (10) as a punch to gain initial access for thetool (10) in windshields, windows or other work pieces in which the workpiece edge is not free. The operator will punch the tips (61) of theblade set (50) generally perpendicularly through such a glass work pieceto form an initial opening and the lead in surface (60) allows thedynamic blade (53) to easily be slipped through such an initial openingto begin shearing operation.

The rear of the dynamic blade (53) includes a coupling (62) to engagewith the reciprocating member, which may be a rotating eccentric cam.The shape of the coupling (62) is specific to the element forming thereciprocation to which it connects, and the illustrated version is oneknown example.

As shown in the FIGS. 4-6, in side view the static blades (51) and (52)have a straight cutting or shearing edge extending back from the bluntedtip (61) extending at a sharp angle from the other side of the bluntedtip (61) to the area of full thickness of the static blade (51 and 52)in the area across from where the shearing occurs such that the shearingis generally occurring at the thicker part of the blades (51 and 52).From this part of the blade (52 and 51) rearward the opposed sides aregenerally parallel as shown. The top or operating edge of the dynamicblade (53) was discussed above. The rear side of the blades (53) extendsat a sharp angle from the other side of the blunted tip (61) fromleading surface (60) to the area of full thickness of the blade (53) inthe area across from the portion (57) where the shearing occurs suchthat the shearing is generally occurring at the thicker part of theblade (53). From this part of the blade (53) rearward the opposed sidesare generally parallel as shown.

In the particular embodiments shown, the left static cutting blade (51)and right static cutting blade (52) of blade set (50) are mounted in aparallel fashion, on the same plane inside the head (40) using theforward (41), middle (42) and aft (43) fastener sets. The static blades(51 and 52) contain a gap (G) equivalent to 0.250 inches.

The forward fastener set (41) provides the pivot for dynamic cuttingblade (53) which contains a bushing (54) in pivot opening (56). Thedynamic cutting blade (53) pivots between the left (51) and right (52)static cutting blades and reciprocates between opened to closedpositions shown in FIGS. 6 and 5, respectively, as powered by the drivesystem (30). The left exterior surface (53 c) of the dynamic cuttingblade (53) rests against the right interior surface (51 a) of the leftstatic cutting blade (51). The right exterior surface (53 d) restsagainst he left interior surface (52 a) of the right static cuttingblade (52). The gap (GL) between the left static cutting blade (51) andthe dynamic cutting blade (53) and the gap (GR) between the right staticcutting blade (52) and the dynamic cutting blade (53) may be between0.005-0.025 inches, respectively.

As discussed above, to allow access to a closed edge work piece W suchas an automobile windshield, the operator gains access to theundersurface of the glass by jabbing the blade tips (60) into thewindshield. When the laminated glass or film-covered glass work piece Wis placed between the static (left—51 and right—52) and dynamic cuttingblade (53) of the blade set (50), the work piece W is cut by theshearing forces developed as the upper cutting surface (53 e) of thedynamic cutting blade (53) is powered to close against the lower cuttingsurfaces of the static cutting blades (left—51 b and right—52 b) of theleft (51) and right (52) static cutting blades.

The chaff generated but the cutting action of the blade set (50) isejected upward from the blade set (50) by the reciprocating action ofthe dynamic cutting blade (53). With the present blade set (50) designof tool (10) the chaff is largely sheared off as a continuous ribbon ofmaterial rather than being shredded into dangerous airborneparticulates. The dust or particulate produced by tool (10) on aautomotive window removal is reduced over 90% from conventional windowcutting (ripping) saws. The chip guiding surface (59) of the cuttingsurface (53 e) can be used to control and guide the chaff. The blade set(50) as shown will minimize air born silica dust which represents anadditional hazard, particularly in windshield replacement applications.

In operation after the initial opening is formed (if needed), theoperator grasps the handle (23) of the housing (20) and activates themotor control switch (22) causing the motor (30) to activate driving thetransmission (32) causing the dynamic cutting blade (53) to reciprocatebetween opened and closed positions at a rate of about 0-2,500 RPM orhigher.

First responders like fire fighters, police and emergency medicalpersonnel often are required to remove the windshield or rear glass togain access to vehicle occupants in need of emergency removal and/ormedical care. Windshield repair/replacement technicians are required tocut the windshield glass to remove intact inspection stickers. Othersinvolved with laminated glass and film-covered glass are required to cutthe glass for a variety of purposes. In each case, the current methodshave increased risk of injury and require significant amounts of time tocomplete. The current embodiment of this laminated glass andfilm-covered glass cutting tool will reduce the risk of injury to atrapped victim or the operator and greatly decrease the time necessaryto perform the activity. Obviously decrease time is important in allenvironments, but in emergency response, decreasing the time thatpersonnel take to reach a crash victim will substantially increase thesurvival rate and generally decrease the overall severity of wounds, asit is well It is well established that the patients chances of survivalare greatest if they receive care within a short period of time after asevere injury, with the period after an injury sometimes referred to asthe “golden hour.” Windshield, passenger and rear windows of mostautomobiles can be removed in about 45 seconds with tool (10), andalmost always less than 1 minute, for quick access to patients or forfurther rescue operations.

In addition to the speed of windshield removal with the tool (10) andthe decrease in silica dust for the operator and patient, the tool (10)allows for one handed operation. This allows the other hand to be used,such as with a glass holding lifter, also known as handheld vacuum cups.Designed specifically for glass handling, vacuum cups are the standardof the glass industry and used by glaziers around the world. Thesevacuum cups put a handle where needed on flat glass, curved or bentglass, auto glass and even some pattern glass. Some cups use a pump tocreate a higher vacuum and thus a more reliable hold. Known vacuum cupmodels, such as available from WPG under the brand name WOOD'SPOWR-GRIP® includes diameters from 1¼ to 10 inches and handles for everykind of glass handling, including fenestration, windshield replacement,processing and more. The tool (10) together with a vacuum cup allows asingle operator (e.g. first responder) to safely and rapidly removeautomobile windows.

The tool is described as particularly useful for window removal forfirst responders or field replacement technicians; however it can beused for other similar articles. As an additional note for fieldreplacement technicians to tool allows the technician to easily trimaround inspection/emission stickers (or passes or other fixed emblems)on the replaced windshield, which sticker containing trimming can haveedges taped with duct tape or the like and the inspection/emissionsticker containing unit left with the vehicle, avoiding the need for theuser to obtain replacements for these immediately.

From the foregoing it will be appreciated that, although specificembodiments of the invention have been described herein for purposes ofillustration, various modifications may be made without deviating fromthe spirit and scope of the invention. For example, the left and rightstatic cutting blades may be attached to the motor unit instead of thehead. Accordingly, the invention is not limited except as by the claims.

What is claimed is:
 1. A hand-held cutting tool, comprising: a housingincluding a grip-able handle; a drive system contained within thehousing and including a motor and transmission; a blade set attached tothe housing and including a pair of static cutting blades protrudingoutward from the housing and a dynamic cutting blade positioned betweenand operatively coupled to the static blades and coupled to thetransmission, wherein operation of the motor will reciprocate thedynamic cutting blade between the static cutting blades.
 2. Thehand-held cutting tool of claim 1 wherein the opposed facing surfaces ofthe pair of static cutting blades are parallel and form a gap distancebetween the opposed facing surfaces of the pair of static cutting bladesis about 0.250 inches.
 3. The hand-held cutting tool of claim 2 whereinthe reciprocating cutting blade has an effective width between 0.165 and0.249 inches.
 4. The hand-held cutting tool of claim 1 wherein thedynamic blade is pivoted to the pair of static cutting blades.
 5. Thehand-held cutting tool of claim 4 wherein the dynamic blade includes apair of shearing cutting edges opposed sides of the dynamic blade, eachone shearing cutting edge of the dynamic blade co-operating with ashearing cutting edge of the one static blade.
 6. The hand-held cuttingtool of claim 5 wherein the dynamic blade is configured to reciprocateat a speed of at least 2,500 RPM.
 7. The hand-held cutting tool of claim5 wherein a gap between the static cutting blades and the dynamiccutting blade is between about 0.005-0.025 inches.
 8. The hand-heldcutting tool of claim 5 wherein generally less than 20% of a distancefrom a tip of each blade to the intersection of the cutting edges of thestatic blades and the dynamic blade in the open position forms a cuttingsection for the tool.
 9. The hand-held cutting tool of claim 5 whereineach blade includes a blunted tip.
 10. The hand-held cutting tool ofclaim 9 wherein a rear surface of each blade extends at an angle fromthe blunted tip to an area of full thickness of the blade across fromwhere the shearing occurs such that the shearing is generally occurringat the thicker part of the blades.
 11. A method of cutting laminatedglass and film-covered glass including the steps of: placing a laminatedglass or film-covered glass work piece in between static cutting bladesand a reciprocating cutting blade of a blade set of a handheld laminatedglass and film-covered glass cutting tool while a lower surfaces of thestatic cutting blades are against an upper surface of the laminatedglass and film-covered glass work piece; and activating a laminatedglass and film-covered glass cutting tool trigger switch which activatesthe reciprocating cutting blade of the laminated glass and film-coveredglass cutting tool from the open to closed position consecutivelyagainst the under surface of the work piece causing work piece cuttingprogressively.
 12. The method of cutting laminated glass andfilm-covered glass of claim 11, wherein the top cutting surface of thedynamic cutting blade and the lower cutting surfaces of the staticcutting blades are straight, flat and/or variable along the length andcontain flat, concave and/or variable surfaces in cross section.
 13. Themethod of cutting laminated glass and film-covered glass of claim 11,wherein each blade includes a blunted tip.
 14. The method of cuttinglaminated glass and film-covered glass of claim 13, wherein work pieceis a automobile windshield or automobile window and the operator gainsaccess to the undersurface of the automobile windshield or automobilewindow by jabbing the blade tips into the automobile windshield orautomobile window.
 15. The method of cutting laminated glass andfilm-covered glass of claim 14, wherein the operator uses a handheldvacuum cups to hold the automobile windshield or automobile window whilecutting the automobile windshield or automobile window.
 16. The methodof cutting laminated glass and film-covered glass of claim 15, whereinthe chaff removed is sheared off as a substantially continuous ribbon ofmaterial.
 17. The method of cutting laminated glass and film-coveredglass of claim 16, wherein the automobile windshield or automobilewindow removed in about 45 seconds.
 18. The method of cutting laminatedglass and film-covered glass of claim 16, wherein generally less than20% of a distance from a tip of each blade to the intersection of thecutting edges of the static blades and the dynamic blade in the openposition forms a cutting section for the tool.
 19. The method of cuttinglaminated glass and film-covered glass of claim 16, wherein a gapbetween the static cutting blades and the dynamic cutting blade isbetween about 0.005-0.025 inches.
 20. The method of cutting laminatedglass and film-covered glass of claim 19, wherein the reciprocatingcutting blade has an effective width between 0.165 and 0.249 inches.